diff --git a/IV/mj-msc.tex b/IV/mj-msc.tex index 59af63a..a13c6af 100644 --- a/IV/mj-msc.tex +++ b/IV/mj-msc.tex @@ -103,12 +103,12 @@ \vfill - Šiuo metu prieinami linijų supaprastinimo algoritmai yra kilę iš - matematikos ir geometrijos, bei yra netinkami lankstiems geografiniams - objektams, tokiems kaip upės ir pakrantės. {\WirM} ištyrė, kaip kartografai - vykdo upių generalizaciją, ir sukūrė algoritmą. Mes realizavome šį + Šiuo metu esami linijų supaprastinimo algoritmai yra kilę iš matematikos ir + geometrijos, bet nėra tinkami lankstiems geografiniams objektams, tokiems + kaip upės ir pakrantės, atvaizduoti. {\WirM} ištyrė, kaip kartografai + atlieka upių generalizaciją, ir sukūrė algoritmą. Mes realizavome šį algoritmą ir išsamiai jį dokumentavome. Mūsų {\WM} realizacija ir - dokumentacija yra nemokami ir laisvai prieinami naudojant PostGIS + dokumentacija yra nemokamos ir laisvai prieinamos, naudojant PostGIS platformą. \end{abstract} @@ -164,7 +164,7 @@ viewed as a task of finding a delicate balance between two competing goals: \end{itemize} Given the discussed complexities with natural features, a fine line between -under-simplification (leaving object as-is) and over-simplification (making a +under-simplification (leaving an object as-is) and over-simplification (making a straight line) needs to be found. Therein lies the complexity of simplification algorithms: all have different trade-offs. @@ -265,7 +265,7 @@ Same rivers, unprocessed but in higher scales (1:\numprint{50000} and river features are so compact that a reasonably thin line depicting the river is touching itself, creating a thicker line. We can assume that some simplification for scale 1:\numprint{50000} and especially for -1:\numprint{250000} are worthwhile. +1:\numprint{250000} is worthwhile. \begin{figure}[ht] \centering @@ -484,7 +484,7 @@ Lack of robust openly available generalization algorithm implementations poses a problem for map creation with free software: there is no high-quality simplification algorithm to create down-scaled maps, so any cartographic work, which uses line generalization as part of its processing, will be of sub-par -quality. We believe that availability of high-quality open-source tools is an +quality. We believe that the availability of high-quality open-source tools is an important foundation for future cartographic experimentation and development, thus it benefits the cartographic society as a whole. @@ -785,7 +785,7 @@ code. Besides testing for specific cases, an automated test suite ensures future stability and longevity of the implementation itself: when new contributors start changing code, they have higher assurance they have not broken -already-working code. +an already-working code. \subsection{Reproducibility} \label{sec:reproducing-the-paper} @@ -811,7 +811,7 @@ example reference for anyone willing to start using the algorithm. \section{Algorithm Implementation} -Like alluded in section~\ref{sec:introduction}, {\WM} paper skims over +As alluded in section~\ref{sec:introduction}, {\WM} paper skims over certain details which are important to implement the algorithm. This section goes through each algorithm stage, illustrating the intermediate steps and explaining the author's desiderata for a more detailed description. @@ -912,7 +912,7 @@ purpose of each column in \textsc{wm\_debug} is described below: When debug mode is turned off (that is, \textsc{dbgname} is left unspecified), \textsc{wm\_debug} is empty and the algorithm runs slightly faster. -\subsection{Merging Pieces of the River into One} +\subsection{Merging Pieces of a River into One} Example river geometries were sourced from OpenStreetMap\cite{openstreetmap} and NŽT\cite{nzt}. Rivers in both data sources are stored in shorter line @@ -988,7 +988,7 @@ table~\ref{table:scale-halfcirlce-diameter}. \subsection{Definition of a Bend} \label{sec:definition-of-a-bend} -The original article describes a bend as: +The original article describes a bend as follows: \begin{displaycquote}{wang1998line} A bend can be defined as that part of a line which contains a number of @@ -1359,7 +1359,7 @@ of exaggeration operator: \end{description} -Both functions are inter-change-able and can be found in listing~\ref{lst:wm.sql}. +Both functions are interchangeable and can be found in listing~\ref{lst:wm.sql}. Figure~\ref{fig:isolated-1-exaggerated} illustrates an exaggerated bend using \textsc{wm\_exaggerate\_bend2}. @@ -1371,9 +1371,9 @@ generalization, and suggests specific improvements. One of our goals is to compare the generalized lines with the official generalized dataset\cite{nzt}. Therefore, we have selected the target scales -that the official sources offer too: 1:\numprint{50000} and +that the official sources offer, too: 1:\numprint{50000} and 1:\numprint{250000}. The \textsc{dhalfcircle} values for the subset are as -follows: +follow: \begin{table}[ht] \centering @@ -1394,7 +1394,7 @@ Our generalized results are viewed from the following angles: \subsection{Generalization Results of Analyzed Rivers} \label{sec:generalization-results-of-analyzed-rivers} -\subsubsection{Medium-scale (1:\numprint{50000})} +\subsubsection{Medium-Scale (1:\numprint{50000})} \label{sec:analyzed-medium-scale} \begin{figure}[h!] @@ -1427,7 +1427,7 @@ Figure's~\ref{fig:salvis-wm75--grpk10-1x50k} left part is clipped to Figure~\ref{fig:salvis-wm75--grpk10-1x50ktl}. As one can see, some bends were well exaggerated, and some bends were eliminated. -Top--right side (clipped in Figure~\ref{fig:salvis-wm75--grpk10-1x50ktl}) some jagged +Top--right side (clipped in Figure~\ref{fig:salvis-wm75--grpk10-1x50ktl}), some jagged and sharp bends appear. These will become more pronounced in even larger-scale simplification in the next section. @@ -1436,7 +1436,7 @@ sharp edges for others. \clearpage -\subsubsection{Large-scale (1:\numprint{250000})} +\subsubsection{Large-Scale (1:\numprint{250000})} \label{sec:analyzed-large-scale} As visible in Figure~\ref{fig:salvis-wm220-10x}, for large-scale map, some of the @@ -1470,7 +1470,7 @@ simplification and overlays the original. A conglomeration of bends is visible, especially in top--right side of the illustration. We assume this was caused by two bends significantly exaggerated, -leaving no space to exaggerate for those between the two. +leaving no space to exaggerate those between the two. \subsubsection{Discussion} @@ -1495,17 +1495,17 @@ future research and improvement: \subsubsection{Background} There are a few datasets used in this comparison: GRPK10, GRPK50 and -GRPK250. They are vector datasets, which include rivers. They can be +GRPK250. They are vector datasets which include rivers. They can be downloaded for free from \cite{nzt}. Here are the meanings of the codenames: \begin{description} - \item[GRPK10] is dataset of highest detail. Suited for maps of scale + \item[GRPK10] is a dataset of highest detail. Suited for maps of scale 1:\numprint{10000}. \item[GRPK50] is suited for maps of scale 1:\numprint{50000}. - \item[GRPK250] offers least detail, and is suited for maps of + \item[GRPK250] offers the least detail, and is suited for maps of scale 1:\numprint{250000}. \end{description} @@ -1515,7 +1515,7 @@ During the analysis, we ran {\WM} on GRPK10 for 2 destination scales: detailed in section~\ref{sec:bend-scaling-and-dimensions}.} This section compares the resulting {\WM}--generalized rivers to GRPK50 and GRPK250. -\subsubsection{Medium-scale (1:\numprint{50000})} +\subsubsection{Medium-Scale (1:\numprint{50000})} For our research location, the national dataset GRPK10 is almost equivalent to GRPK50, with a few nuances. Figure~\ref{fig:salvis-wm75-grpk50-grpk10-1x50k} @@ -1552,7 +1552,7 @@ implementation. \clearpage -\subsubsection{Large-scale (1:\numprint{250000})} +\subsubsection{Large-Scale (1:\numprint{250000})} \label{sec:national-large-scale} Figure~\ref{fig:salvis-wm220} illustrates the original GRPK250 and the @@ -1582,7 +1582,7 @@ desired in section~\ref{sec:future-suggestions}. \subsection{Comparison with {\DP} and {\VW}} It is time to visually compare our implementation with the classical -algorithms: {\DP}, {\VW} and Chaikin. Since we have established more work is +algorithms: {\DP}, {\VW} and Chaikin. Since we have established that more work is needed for small-scale maps (1:\numprint{250000}), we will limit the comparison in this section to 1:\numprint{50000}. @@ -1675,9 +1675,9 @@ implementation: limits are necessary. \item Research when bends should be marked as \textsc{isolated}. As is - seen from examples, the current criteria is not robust enough. + seen from examples, the current criteria are not robust enough. - \item Once the points above yield a satisfactory result, efficiency of the + \item Once the points above yield a satisfactory result, the efficiency of the algorithm could be improved to work on the lines in "streaming" fashion (more details in section~\ref{sec:algorithm-implementation-process}). @@ -1716,7 +1716,7 @@ This section contains code listings of the {\WM} algorithm. \subsection{Re-Generating This Paper} \label{sec:code-regenerate} -Like explained in section~\ref{sec:reproducing-the-paper}, illustrations in +As explained in section~\ref{sec:reproducing-the-paper}, illustrations in this paper are generated from a small list of sample geometries. To observe the source geometries or regenerate this paper, run this script (assuming the name of this document is \textsc{mj-msc-full.pdf}).